One of the most famous flash diets is called the “egg diet” : it consists of eating two hard-boiled eggs for breakfast with half a grapefruit, and for lunch and dinner fish or lean meat with a plate of vegetables ( source ). Nothing else. Also known as the Thatcher Diet , the egg diet made a comeback following the acquittal of eggs from allegations of causing high cholesterol ( source ), and in particular after a study in a sample of obese women found that in a diet with two eggs a day every day not only did the cholesterol not rise, but the women lost weight and were full until lunch ( source ).

This is because two whole eggs, eaten for breakfast, satiate despite being low-calorie, and do not make you feel hungry even after three hours. In short: the classic English breakfast based on eggs would not be so harmful to health compared to how we imagine it, as long as we avoid bacon and sausages! 
Now let’s see a healthier version of the egg diet: the classic scheme promises a very rapid weight loss, of several kilos in a week (up to 4-5). Clearly, the trick to rapid weight loss is soon said: you lose a lot of fluids because it’s a ketogenic diet, but there are no contraindications to doing it for a week or two (source).
The important thing is that in the week following the end of the diet the carbohydrates are restored with criteria and little by little : first by adding two more portions of fruit to the scheme, then re-establishing a healthy Mediterranean diet.
Even in this healthier version, the egg diet is a disposable diet or fad diet: for this reason it is not recommended to undertake it without the supervision of your doctor.
On page two the very simple and healthiest plan to do it without risk , and losing a maximum of 2 kilos per week.